Emerson Rosemount 3100 Series, Reference Manual, Page: 28 / 144

Reference Manual
00809-0100-4840, Rev. BA
July 2008
Rosemount 3100 Series
3-12
Relay number 2 is defaulted as a 'fault' relay - normally energized - but may
be re-configured on-site as a set-point relay if required.
Relay status indicators are on the LCD inside the housing (see “Display and
Push-buttons“ on page 4-2.)
Wiring for The
Rosemount 3105
The Rosemount 3105 is for intrinsically safe installations. See Appendix B for
the safety approvals and control drawings for the Rosemount 3100 Series.
NOTE!
Make sure the power supply is off when connecting the transmitter.
If HART
®
digital communications is required, see “Wiring to Allow HART
®
Communication“ on page 3-14.
NOTE!
Make sure that the instruments in the loop are installed according to
intrinsically-safe field wiring practices and control drawings, when applicable.
Installation In a Non-hazardous Area
For non-hazardous (Ordinary Location) installations, wire the transmitter as
shown in Figure 3-9.
Installation In a Hazardous Area
When The 3105 is used with a Rosemount 3490 Series Control Unit,
NO additional safety barriers are required as the output from the control unit is
Intrinsically Safe. In this case, wire the transmitter as shown in Figure 3-9.
If powering the transmitter from any other power supply, ensure a suitable
Intrinsically Safe barrier is fitted in the non-hazardous (safe) area.
The barrier must be chosen such that its output parameters Uo, Io and Po are
less than Ui, Ii and Pi of the transmitter (see Appendix B).
In addition, the sum of the capacitance and the inductance of the transmitter
and the connecting cable fitted must not exceed the maximum specified for
the barrier chosen.
Table 3-4.
Connections for The 3105
Connections
Terminal 1 24 Vdc
Terminal 2 0 Vdc
Terminal 7 Remote temperature sensor (if used) - see page 3-14
Terminal 8 Remote temperature sensor (if used) - see page 3-14
Earth Screen Connect to a ground (earth) in the control room.